Notophthalmus perstriatusStriped Newt

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Geographic Range

Striped newts are endemic to southeastern Georgia and north-central Florida, where their range extends as far west as Tallahassee and as far south as Orlando. ("Petition to list the Striped Newt, {Notophthalmus perstriatus}, as a federally threatened species under the Endangered Species Act of 1973", 2008; Dodd, Jr., 1993; Wilson, 1995)

Habitat

Striped newt habitats include pine flatwoods, sandhills, and xeric hammocks. They are well-adapted for burrowing and live underground. This species can often be found under fallen trees and old stumps as well. During their breeding season, these newts rely on temporary water sources such as sinkhole or bay ponds. Quite often, their terrestrial habitat is not in close proximity to the pond in which they choose to breed. ("Distribution and status of the striped newt and Florida gopher frog in peninsular Florida", 1999; Dodd, Jr. and Cade, 1998; Jensen, et al., 2008; Wilson, 1995)

  • Aquatic Biomes
  • temporary pools
  • Average elevation
    153 m
    501.97 ft

Physical Description

Adult striped newts range from 5.1 to 10.5 cm in total length and weigh an average of 0.8 g. This species usually has an olive green or brown coloration with a yellow belly and two red stripes that run down its back. Some individuals also have red spots adjacent to their stripes, or black spots covering their belly. These newts possess no costal grooves and no distinct cranial ridges. When inhabiting aquatic environments they develop smooth skin and a tail fin. Once they return to terrestrial habitats, the tail fin is lost and their skin becomes coarse. They have slim legs, with the hind legs being larger in males than in females. Males also have excrescences on their legs and feet, and an orange glandular cluster in the vent area. This glandular structure is absent in females. In other respects, males and females are physically similar. Striped newts have four toes on their front feet and five toes on their hind feet. ("Petition to list the Striped Newt, {Notophthalmus perstriatus}, as a federally threatened species under the Endangered Species Act of 1973", 2008; Altig and Ireland, 1984; Dodd, Jr., 1993; Jensen, et al., 2008; Johnson, 2005; Wilson, 1995)

Striped newt hatchlings are approximately 8 mm in length from snout to tail. They have two dark stripes that span the length of their body, but these stripes fade away a week after they hatch. Hatchlings do not have legs. The larvae develop two new dark stripes soon after the others fade away. Their bodies are usually green to dark gray in color, with a pale yellow belly. Hatchlings also have bushy external gills and black spots on their tail. Their skin is very smooth. Striped newts also exhibit an eft stage, at which point they leave their natal pond as a sexually immature adult. This stage occurs as early as 3 months of age, and is characterized by an orange to red body coloration with red stripes. Efts have rough skin and are 40 to 50 mm long. (Altig and Ireland, 1984; Johnson, 2005)

Striped newts are sometimes mistaken for eastern newts (Notophthalmus viridescens). Both species are roughly the same color, have rough skin in their adult stage, and lack costal grooves. However, instead of stripes, eastern newts have red spots on their backs and are also larger than striped newts. (Jensen, et al., 2008)

  • Sexual Dimorphism
  • sexes alike
  • Average mass
    0.8 g
    0.03 oz
  • Range length
    5.1 to 10.5 cm
    2.01 to 4.13 in

Development

Striped newt development occurs in two different ways. In most cases, aquatic larvae develop into terrestrial efts, which are immature larvae that have recently metamorphosed. Larvae usually metamorphose by the time they are three months old, at which time they leave their aquatic habitats. While in their terrestrial habitat, they fully develop into a sexually mature adult and lose the remnants of their gills. The second type of development occurs when breeding ponds do not dry out as they normally do. Instead of becoming efts, larvae become paedomorphs, which are sexually mature larvae, inhabiting the pond until the next breeding period. After breeding for the first time, paedomorphs lose their gills and transition to terrestrial habitats as adult newts. ("Petition to list the Striped Newt, {Notophthalmus perstriatus}, as a federally threatened species under the Endangered Species Act of 1973", 2008; Dodd, Jr. and Cade, 1998; Jensen, et al., 2008; Johnson, 2002; )

Reproduction

Nothing is known about the mating systems of striped newts. In a related species (Notophthalmus viridescens), males either capture a female around the neck with their hindlimbs or perform displays until a female becomes receptive to mating. Males usually do not mate with more than two females in one breeding season. (Verrell, 1985)

Striped newts become sexually mature at 8 to 24 months of age. Breeding begins in late autumn and can last until early spring. This species breeds in temporary ponds that are free from predators such as fish. Preferred ponds have a tree canopy that provides shade yet allows some sunny areas, and are less than 1.5 m deep. Not much is known about the actual breeding behavior of the species, except that they have a protracted courtship. Eggs are layed one at a time and it can take several months for a female to finish laying all of her eggs. The eggs are adhesive, and are attached to aquatic plants as they are layed. The total number of eggs that may be laid by an individual is not currently known. Except in the case of severe drought, striped newts return to the same pond each year to breed. Because of the unpredictability of their breeding habitats, they may sometimes alter the time that they migrate to breed. ("Distribution and status of the striped newt and Florida gopher frog in peninsular Florida", 1999; "Petition to list the Striped Newt, {Notophthalmus perstriatus}, as a federally threatened species under the Endangered Species Act of 1973", 2008; Dodd, Jr. and Cade, 1998; Dodd, Jr., 1993; Jensen, et al., 2008; Johnson, 2002)

  • Breeding interval
    Striped newts breed once yearly, between late fall and early spring.
  • Breeding season
    Mating and fertilization occur between late fall and early spring. Egg laying may take several months due to the fact that eggs are laid one at a time.
  • Range age at sexual or reproductive maturity (female)
    8 to 24 months
  • Range age at sexual or reproductive maturity (male)
    8 to 24 months

Female striped newts hide each egg by wrapping it in the leaf of an aquatic plant. No further parental investment is provided. (Jensen, et al., 2008; Johnson, 2002)

Lifespan/Longevity

Striped newts usually live from 12 to 15 years in the wild and in captivity. Their average life span is reported as 12.9 years. (Dodd, Jr., 1993; de Magalhaes and Costa, 2009)

  • Typical lifespan
    Status: wild
    12 to 15 years
  • Average lifespan
    Status: wild
    12.9 years

Behavior

Little is known about the behavior of striped newts. In terrestrial habitats, they are fossorial and exhibit cryptic behavior. Most of the studies examining the behavior of striped newts focus on their movement to and from their breeding habitats. They usually move to ponds during late fall and winter, but have also been known to immigrate to breeding ponds nearly year-round, depending on conditions. Adults emigrate from breeding ponds in the late spring. While there is constant movement in and out of the ponds from winter to spring, most of the movement occurs during particular periods. Large numbers of sexually mature newts tend to immigrate to a particular breeding pond at the same time, often in a series of several immigration periods. Emigration follows the same pattern. During some periods, large numbers of mature adult newts emigrate and at other times, efts make up the majority of the newts leaving a pond. Several papers provide contrasting information as to which direction they move; some say it is random while others claim their movement is non-random. Movement can also be greatly affected by conditions such as drought. During these times, newts will immigrate to ponds at any sign of rain. Few newts adhere to regular movement patterns into and out of a pond due to the variable hydroperiod, and those that do usually do not survive. ("Distribution and status of the striped newt and Florida gopher frog in peninsular Florida", 1999; Dodd Jr., et al., 2005; Dodd, Jr. and Cade, 1998; Dodd, Jr., 1993; Johnson, 2002; Johnson, 2003)

Home Range

Striped newts typically move approximately 160 meters from their breeding ponds to the surrounding forests, but they have been shown to travel as far as 500 to 700 meters. Individuals do not maintain or defend particular territories. ("Petition to list the Striped Newt, {Notophthalmus perstriatus}, as a federally threatened species under the Endangered Species Act of 1973", 2008)

Communication and Perception

Little is known about how striped newts communicate with conspecifics. It is known that they heavily rely on their sense of smell and sight to perceive their environment, especially when tracking prey. Larval newts also have a lateral line similar to that of fishes, with which they can detects vibrations in the water. While there have not been many studies of this species, research on eastern newts (Notophthalmus viridescens) may give insight into how striped newts feed. Eastern newts first detect potential prey with their keen eyesight. To determine if the object is edible, they first touch it with their snout and smell it. After determining that what they have found is acceptable, they will snap at the prey and consume it. Other studies on the eastern newt showed that during the mating season, males showed a preference for female odors, indicating that olfaction also plays an important role in mating and communication between sexes. (Brodie, 1977; Christman and Franz, 1973; Jorgensen, 2000)

Food Habits

Striped newts are opportunistic feeders. As larvae, they feed on small aquatic invertebrates. As efts, they eat small terrestrial invertebrates. As adults, their diet is influenced by the season. During breeding periods, they usually forage at the bottom of the breeding pond, eating invertebrates such as fairy shrimp, amphibian eggs, and tadpoles. On land, they have been known to eat spiders, small insects, worms, and snails. Observations of their feeding habits have shown that most of their prey range from 6-10 mm in size. Unlike other newt species, striped newts do not normally eat their shed skin. (Christman and Franz, 1973; Dodd Jr., et al., 2005; Jensen, et al., 2008; Wilson, 1995)

  • Animal Foods
  • amphibians
  • eggs
  • insects
  • terrestrial non-insect arthropods
  • mollusks
  • terrestrial worms

Predation

Little is known regarding specific predators of striped newts. Larvae are preyed upon by a variety of aquatic creatures, including dragonfly larvae or fish, when they are present in breeding pools. Predators of adult striped newts include mole salamanders (Ambystoma talpoideum), snakes, and birds. (Dodd Jr., et al., 2005; Jensen, et al., 2008)

Striped newts exhibit several different antipredatory behaviors. Their dorsal coloration is cryptic in the environments that they inhabit. When they feel threatened, they become immobile and assume the “unken” position by raising their tail and head. While the upper half of their body is drab, their underside is a brighter color. This posture allows them to show off this aposematic coloration. While in this position, the striped newts also produce noxious skin secretions. While the exact toxin in these excretions is not currently known, it is thought to be tarichatoxin, a neurotoxin that is secreted by other species in the genus Notophthalmus. This toxin has been found in all stages of life, from larvae to adult. Toxins may also be used as protection against external parasites. (Brodie, 1977)

  • Known Predators

Ecosystem Roles

Striped newts serve as prey items to mole salamanders (Ambystoma talpoideum), birds, and snakes. They act as predators of small invertebrates, insects, snails, and worms in both terrestrial and temporary aquatic habitats. Studies examining parasites of this species have yet to be performed. (Brodie, 1977; Christman and Franz, 1973; Dodd Jr., et al., 2005; Jensen, et al., 2008; Wilson, 1995)

Economic Importance for Humans: Positive

For a brief period in the 1970s and 1980s, striped newts were sold as pets in Florida. Since that time, there have been no records of this species being kept and sold as a pet. ("Petition to list the Striped Newt, {Notophthalmus perstriatus}, as a federally threatened species under the Endangered Species Act of 1973", 2008)

Economic Importance for Humans: Negative

As a defense mechanism, striped newts secrete a toxin that, when ingested, can result in a number of medical problems including paralysis and death. (Brodie, 1977; Dodd Jr., et al., 2005; Riston-Williams, et al., 2006)

Conservation Status

Striped newts are listed as "near threatened" by the IUCN Redlist due to habitat loss. Their terrestrial habitats are being destroyed for agricultural and residential purposes, while their aquatic habitats are being depleted and used as a water source for humans. Many are also killed while migrating across highways. (Hammerson and Dodd, 2011)

Although there are no protective regulations currently in place for this species, striped newts are considered to be "Imperiled in Florida" by the Florida Natural Areas Inventory and "Rare" by the Florida Committee on Rare and Endangered Plants and Animals. They are also considered to be rare in Georgia, the other state in which they are found. (Dodd Jr., et al., 2005)

Contributors

Patricia Holland (author), Radford University, Karen Powers (editor), Radford University, Kiersten Newtoff (editor), Radford University, Melissa Whistleman (editor), Radford University, Jeremy Wright (editor), University of Michigan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

acoustic

uses sound to communicate

aposematic

having coloration that serves a protective function for the animal, usually used to refer to animals with colors that warn predators of their toxicity. For example: animals with bright red or yellow coloration are often toxic or distasteful.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

freshwater

mainly lives in water that is not salty.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

insectivore

An animal that eats mainly insects or spiders.

internal fertilization

fertilization takes place within the female's body

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

metamorphosis

A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.

migratory

makes seasonal movements between breeding and wintering grounds

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

poisonous

an animal which has a substance capable of killing, injuring, or impairing other animals through its chemical action (for example, the skin of poison dart frogs).

polygynous

having more than one female as a mate at one time

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

visual

uses sight to communicate

References

Florida Game and Freshwater Fish Commission. Distribution and status of the striped newt and Florida gopher frog in peninsular Florida. NG90-035. Florida: Nongame Wildlife Program. 1999.

Coastal Plains Institute and Land Conservancy. Petition to list the Striped Newt, {Notophthalmus perstriatus}, as a federally threatened species under the Endangered Species Act of 1973. None. Tallahassee, Florida: U.S. Fish and Wildlife Service. 2008.

Altig, R., P. Ireland. 1984. A key to salamader larvae and larviform adults of the United States and Canada. Herpetologica, 40/2: 212-218.

Brodie, E. 1977. Salamander antipredator postures. Copeia, 1977/3: 523-535.

Christman, S., L. Franz. 1973. Feeding habits of the striped newt, (Notophthalmus perstriatus). Journal of Herpetology, 7/2: 133-135.

Dodd Jr., C., D. Means, S. Johnson. 2005. Notophthalmus perstriatus Bishop, 1941. Pp. 887-889 in M Lannoo, ed. Amphibian Declines: The Conservation Status of United States Species. Berkeley, CA: University of California Press.

Dodd, Jr., C. 1993. Cost of living in an unpredictable environment: The ecology of striped newts (Notophthalmus perstriatus) during a prolonged drought. Copeia, 1993/3: 605-614.

Dodd, Jr., C., B. Cade. 1998. Movement patterns and the conservation of amphibians breeding in small, temporary wetlands. Conservation Biology, 12/2: 331-339.

Hammerson, G., K. Dodd. 2011. "The IUCN Red List of Threatened Species" (On-line). Accessed February 10, 2012 at http://www.iucnredlist.org/apps/redlist/details/14872/0.

Jensen, J., C. Camp, W. Gibbons, M. Elliot. 2008. Amphibians and Reptiles of Georgia. Georgia: University of Georgia Press.

Johnson, S. 2005. Conservation and Life History of the Striped Newt: The Importance of Habitat Connectivity. Pp. 91-98 in W Meshaka, K Babbitt, eds. Status and Conservation of Florida Amphibians and Reptiles. Malabar, FL: Kreiger Publishing.

Johnson, S. 2002. Life history of the striped newt at a north-central Florida breeding pond. Southeastern Naturalist, 1/4: 381-402.

Johnson, S. 2003. Orientation and migration distances of a pond-breeding salamander ({Notophthalmus perstriatus}, Salamandridae). Alytes, 21/1: 3-22.

Jorgensen, C. 2000. Amphibian respiration and olfaction and their relationships: from Robert Townson (1794) to the present. Biological Review, 75: 297-345.

Riston-Williams, R., M. Yotsu-Yamashita, V. Paul. 2006. Ecological functions of tetrodotoxin in a deadly polyclad flatworm. Proceedings of the National Academy of Sciences in the United States of America, 103/9: 3176-3179.

Verrell, P. 1985. Female availability and multiple courtship in male red-spotted newts, Notophthalmus viridescens (Amphibia): Decisions that maximize male mating success. Behaviour, 94/3&4: 244-253.

Wilson, L. 1995. Land Manager's Guide to the Amphibians and Reptiles of the South. Chapel Hill, North Carolina: The Nature Conservancy.

de Magalhaes, J., J. Costa. 2009. A database of vertebrate longevity records and their relation to other life-history traits. Journal of Evolutionary Biology, 22/8: 1770-1774.